Magnetically suspended toy top



Juy 1 96 A. STARKENBERG MAGNETICALLY SUSPENDED TOY TOP Original Filed Dec. 23, 1963 INVENTOR. ARNOLD STARKENBERG BY M 2' 20} ATTORNEYS United States Patent 3,330,067 MAGNETICALLY SUSPENDED TOY TOP Arnold Starkenherg, Roclraway, N.Y., assignor to American Magnetop Corporation, Brooklyn, N.Y., a corporation of New York Continuation of application Ser. No. 332,550, Dec. 23,

1963. This application Feb. 18, 1966, Ser. No. 541,869 Claims. (Cl. 46-242) This is a continuation of application 332,550, filed Dec. 23, 1963, now abandoned.

My invention relates to a toy, and more particularly to a top having a magnetic spindle combined with a magnetic pick-up attached to the end of a line that permits the user to pick-up, manipulate and transfer the top to other surfaces, lines and edges while it is spinning Without appreciably decreasing the rotational momentum of the top.

Hand tops are of course very old in the art. Usually a string is spirally wound about the body of the top and the top is then released with a quick pull of the hand to spin the top about a spindle at the bottom of the top. To a top of this conventional type I have added an upper spindle which is permanently magnetized. This magnetized upper spindle adds another dimension to the enjoyment of a top because it permits the person playing with it to pick it up at this spindle with a magnetic pick-up means which may conveniently (but need not necessarily) be attached to the string used to wind the top. The pick-up means is preferably freely rotatable to allow the top to spin freely on its axis of rotation with no appreciable loss of rotational momentum. The top can be easily transferred to other magnetic surfaces, edges or magnetic wires (such as an ordinary coat hanger) by manipulating this pick-up means properly to suspend it while it spins.

It will be appreciated that either the pick-up means or the spindle means may be the permanently magnetized member, so long as the other device is of magnetic material. Furthermore I have found that certain configurations of the pick-up means and upper spindle are advantageous as will be described later.

The principal object of my invention therefore is to provide an interesting, amusing and educational toy which combines a new and unique magnetic pick-up feature to a spinning top.

A more specific object of my invention is to provide a means for easily picking up a spinning top and transferring it so as to suspend it from various types of magnetic spinning surfaces, lines'and edges without lessening its rotational momentum for the added fascination of the person playing with it.

A further object of my invention is to provide a means for fixing the magnetic suspending means to a top and to provide a magnetic pick-up which is freely rotatable and therefore does not appreciably lower the rotational m0- mentum of the spinning top.

These objects and other objects of my invention not at this time more particularly enumerated will be apparent from the accompanying description and drawings wherein:

FIGURE 1 is a perspective view of one form of my complete toy;

FIGURE 2 is a cross-sectional view through the central axis'of the toy shown in FIG. 1, the toy being shown wth the pick-up means in engagement with the top;

FIGURE 3 is a cross-sectional view through the central axis of an alternative form of the magnetic pick-up means which may be employed in my invention;

FIGURES 4a, b are cross-sectional views through the central axis of another alternative form of the magnetic pick-up means employed in my invention; and

FIGURE 5 is a cross-sectional view through the central axis of an alternative form of an upper magnetic spindle which may be employed in my invention.

Referring to FIGURE 1 my toy may comprise a conventional top generally designated 10 having a central bod 11, and a lower spindle 12. It is provided with an upper spindle 13 on the axis of rotation generally designated 14. String 15 is spirally wound about body 11 in the manner well known in the art and rapidly unwound by a sharp pull of the hand to spin top 10 on spindle 12 about axis 14.

Top body 11 and lower spindle 12 may be fabricated of any suitable non-magnetic material such as plastic, wood or aluminum. Body 11 is preferably shaped to be convenient for winding and unwinding of string 15 and to have a high moment of inertia about axis of rotation 14. Upper spindle 13 is made of a permanently magnetized material shaped in a configuration to be described below in detail.

These parts may be fabricated and assembled in many different ways, but I have found particularly advantageous an asembly wherein top body 11 is formed of a styrene-type plastic in the hollow pointed generally ellipsoidal shape shown in FIGURE 1. The bottom of body 11 is provided with flat surface 16. Extending inwardly from fiat 16 is tube 17 which is coaxial with axis 14 and may be molded integrally with body 11. Snugly fitting into tube 17 is the upper end of lower spindle 12 which seats into body 11 by butting shoulder 18 against flat 16. Lower spindle 12 and tube 17 may also be made of a styrene-type plastic; spindle 12 is preferably solid to improve its strength and wear characteristics. Spindle 12 may be glued into position in body 11 by any suitable plastic solvent cement, or may be a press fit for use of alternate spindles.

Top body 11 is provided with circumferential ridge 23 extending outwardly from flat 22 which serves as a positioner for the first few turns of string 15 about body 11 in the above described manner. At the upper end of body 11 is a raised flat surface generally designated 22 which forms a cylindrical surface designated 23 which may be used. as a convenient surface against which an end loop of string 15 may be held when starting winding string 15 about the body 11. Flat 22 is provided with an axially located pocket 24. Snugly fitting into pocket 24 is the central portion of spindle 13. Spindle 13 may be glued to body 11 in this position by any suitable plastic solvent cement in a manner similar to that employed with lower spindle 12.

Upper spindle 13 may be made of any suitable magnetized material. I have found especially satisfactory an Alnico bar magnet 'sized to fit tightly in pocket 24 with the exposed end shaped like a cone. I have found that it is better to shape the exposed end in the form of a cone with an enclosed angle varying from 45 to 60. Angles substantially greater or smaller than this produce significantly poorer results as will be explained below.

Equally important to my invention is the magnetic pick-up generally designated 31 which is preferably attached to one end of string 15 as shown in FIGURES l and 2, although it may be held separately on a rod or flat surface or elsewhere, as desired. Pick-up 31 is shown in alternative forms in FIGURES 3, 4 and 5.

Referring to FIGURE 2, pick-up 31 has as its central element a magnetic ball 32 which is partially enclosed by and free to rotate in non-magnetic socket 3'3. Attached to the top of socket 33 is a freely rotatable connecting line 34 that connects pick-up 31 to string 15.

As above indicated pick-up 31 may take many forms. I have found especially advantageous the form shown in FIGURE 2 wherein ball 32 is made of a magnetic Permalloy type of stainless steel. Socket 33 comprises loose- 3 fitting collar made of a non-magnetic material suc as plastic, brass or aluminum. Collar 35 has a molded or swedged loosely fitting bearing surface through which a portion of ball 32 extends as shown in FIG. 2. Socket 33 is closed at the top by cap 36 also fabricated of a similarly non-magnetic material. Cap 36 may be attached to collar 35 by a plastic solvent cement if the parts are made of plastic, or if they are made of metal by a suitably brazed or soldered connection.

It is important to the best operation of my toy that ballj32 be free to rotate inside socket 33 with a portion exposedto permit easy rotatable engagement with upper spindle 13 along axis of rotation 14 of the top.

Socket 33 is suspended from string 15 by means of the rotatable connecting link 34 which may also be-made in many different forms. One most suitable arrangement is to provide a hole in cap 36 through which the lowest depending bead of bead chain 41 passes. Hole .0 is prefera'bly chamfered as shown in FIGURE 2 to provide a smooth surface against which the bead chain 41 rotatably bears. One practical manner of making this connection when plastic is used is to mold hole 40 sufliciently large to pass chain 41 through freely. Then with the lowest bead'of bead chain 41 in the position shown in FIGURE 2, cap 36 is heated to flow the material on the surface to thereby constrict hole 40 and thus lock the lowest bead of head chain 41 inside cap 36. The upper end of bead chain 41 may then be mechanically clamped to one end of string 15. r

7 Alternative forms of pick-up 31 are illustrated in FIGURES 3 and 4. Referring to FIGURE 3, a unitary socket 33 is illustrated with a single bead 45 and chain 46 suspension, the chain 46 being sized to rotate freely in perforation 47 of socket 33. Another satisfactory, arrangement is shown in FIGURES 4a, b; it employs socket 33 which comprises a U-shaped bearing race 50 for holding a freely rotatable ball 32. Race 50 is rotatably suspended from bead chain 46.

It should be understood that the particular form used in making my toy is not critical. What is important is that the magnetic force between ball 32 and upper spindle 13 must be suflicient to support the weight of top 10. Either ball 32 or spindle 13 (or both) may be magnetized so long as the other is magnetic. Also important is the freedom of rotation of both ball 32 with respect to socket 33'and socket 33 with respect to string 15. Ball 32 must be free to turn its point of contact with upper spindle 12 to bring it into coincidence with axis of rotation 14 and thus avoid undesired precession effects. This is especially important when ball 32 first contacts spindle 13. Socket 33 must 'be free to rotate about string 15 to avoidrwinding tend to slow the speed of rotation of top'10.

' Another important factor is the shape .of upper spindle 13. If it is needle-shaped the magnetic lines of force are 'too constricted to permit the use of a magnet for spindle 13 of practical size. If on'the other hand the conical shape of spindle'13 approaches a flat surface the magnetic lines of force are too diffuse and therefore tend to cause the ball 32 to contact spindle 13 along its surface rather than at the point. Point contact is necessary since only the point of spindle 13 lies on the axis of rotation 14, and suspension on this axis is pre-requisite to the avoidance of protection of the point of spindle 13. I have found that the point of spindle 13 is subject to brittle fracture if it is thrown on a hard surface such as concrete, particularly when spindle 13 is made of Alnico. Cap 51 protects against this fracture and does not appreciably diffuse the 4 magnetic lines of force emanating from the point of spindle 13.

In operation string 15 is spirally Wound about body 11, and the top 10 is caused to spin on lower spindle 12 by the familiar sharp pulling action of the users hand.

After top 10 assumes its upright spinning position, it may be picked up by lowering the magnetic pick-up 31 into contact with upper spindle 13. Top 10 may then be manipulated at the end of string 15 in any manner desired or it may be transferred to another magnetic surface, wire or edge to achieve other desired and interesting effects. This pick-up arrangement is not only useful for increasing the dimensions of play with a spinning top while it is moving, it also provides a very simple and convenient device for picking up the top after its spin is finished. 7

My toy also has significant educational value since it adapts itself very well to the demonstration of gyroscopic principles. My toy can be made to'swing about a string of the string when it suspends top 10 since this would in a manner to illustrate precessional effects and to traverse a linear path to show inertial eflects. Thus it can serve as a fascinating study aid to one who is studying these properties.

While this description has dealt with particular embodiments of my invention it must be understood that' other embodiments and improvements to my'basic .in-

vention will be apparent to those skilled inthe art. Therefore, while I have described certain embodiments with particularity it must be understood that I do not intend to be limited by the foregoing description but solelyrby the claims granted.

What is claimed is:

1. A spinning top having an upper spindle as an upper end portion and a lower spindle as a lower end portion, a

7 body between the two end portions having a continuous extended string wrapping surface extending therebetween adapted to receive successive turns of an operating pull string, said surface being of a generally inverted conical shape, the smaller portion of which terminates in said lower spindle, the axis of rotation about which said top dle and upper spindle on the axis of rotation of said top and a body between said spindles about which a string may be wound and rapidly released to impart rotation sufiicient to spin said top on said lower spindle, said upper spindle being a permanent magnet, and a releasable pickup means comprising a sphere of ferromagnetic material,

said sphere and upper spindle having suflicient magnetic force when in contact with each other to support the weight of said top, and socket means loosely housing said magnetic sphere, said socket means having an opening through which part of said sphere extends and a relatively frictionless bearing surface centered around said opening for loosely, retaining said sphere in said socket 3. A toy comprising a top having a lower spindle and upper spindle on the axis of rotation of said top and a body between said spindles about which a string may be wound and rapidly released to impart rotation sufficient to spin said top'on said lower spindle, saidupper spindle being a permanent magnet, and a releasable pick-up means comprising a sphere of ferromagnetic material, said sphere and upper spindle having suflicient magnetic force when in contact with each other to support the weight of said top, a socket to loosely house said sphere, said socket having an opening through which part of said sphere extered around said opening for loosely retaining said sphere in said socket, and linear suspending means attached to said socket opposite said opening.

4. A hand top toy comprising a top body having a lower spindle and an upper spindle, said upper spindle being a permanent magnet, string which may. be wound around said top body and rapidly released to impart rotation sufiicient to spin said top on said lower spindle, freely rotatable link means attached to said string, a sphere retaining socket attached to said link means, said socket having an opening at one end and a relatively frictionless bearing surface around said opening for loosely retaining a sphere in said socket, and a sphere of ferromagnetic material freely rotatable inside said socket with a part of said sphere extending through said opening, said sphere and upper spindle having suflicient magnetic force to support the weight of said top when the sphere is in contact with said upper spindle.

5. A hand top improvement comprising a permanently magnetic spindle mounted on the upper end of a top coaxial with the axis of rotation of said top, releasable pickup means comprising a ferromagnetic sphere, said sphere and spindle having sufficient force when in contact with each other to support the weight of said top, a socket to loosely house said magnetic sphere, said socket having an opening through which part of said sphere extends and a relatively frictionless bearing surface centered around said opening for loosely retaining said sphere in said socket, and rotatable connecting link attached to said socket opposite said opening, the free end of said link being attached to the string used to spin said top.

References Cited UNITED STATES PATENTS 960,715 6/ 1910 Schneider 46-241 1,411,974 4/ 1922 Mann 46-242 2,142,299 1/1939 Begood 46-64 2,523,351 9/1950 Armstrong.

2,535,157 12/1950 Radovan 46-7O 2,639,546 5/ 1953 Shockey 4661 X 3,118,669 l/ 1964 Merrill 46-242 X F. BARRY SHAY, Primary Examiner. RICHARD C. PINKHAM, Examiner. R. F. CUTTING, Assistant Examiner. 

4. A HAND TOP TOY COMPRISING A TOP BODY HAVING LOWER SPINDLE AND AN UPPER SPINDLE, SAID UPPER SPINDLE BEING A PERMANENT MAGNET, STRING WHICH MAY BE WOUND AROUND SAID TOP AND BODY AND RAPIDLY RELEASED TO IMPART ROTATION SUFFICIENT TO SPIN SAID TOP ON SAID LOWER SPINDLE, FREELY ROTATABLE LINK MEANS ATTACHED TO SAID STRING, A SPHERE RETAINING SOCKET ATTACHED TO SAID LINK MEANS, SAID SOCKET HAVING AN OPENING AT ONE END AND A RELATIVELY FRICTIONLESS BEARING SURFACE AROUND SAID OPENING FOR LOOSELY RE- 